SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '555e8c88a5565a07f2afb5d1ff437ab945022026cbecbe4b562e79557c8b55ab' 
  AND token = 'fpGSqHyOJ5RcJvuRb1Q15+Ndu+bWn3btVRJH0wSzczA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}